Mother of Devon school girl Charlotte Shaw appeals decision over her death on Ten Tors training expedition

The mother of a teenager swept to her death during training for the Ten Tors expedition has launched a last-ditch bid to prove that her daughter's school was to blame.

Charlotte Shaw, 14, died in March 2007 as she struggled to help a friend while crossing Walla Brook, on Dartmoor, drowning in front of her friends after she was caught up in a powerful stream of water.

Her mother, Jennifer Wilkin-Shaw, has been fighting for five years to establish liability on the part of her daughter's private school, in Bideford, alleging negligence in the way the route march was planned and executed.

She claimed £350,000 in damages from Kingsley School Bideford Enterprises Ltd – formerly known as Edgehill College Enterprises Ltd – which has steadfastly denied responsibility.

Ms Wilkin-Shaw's claims were mainly directed at language teacher, Christopher Fuller, who supervised the group of 11 teenagers, but he was exonerated by High Court judge, Mr Justice Owen, in June last year.

The judge said Mr Fuller had urged the pupil leading the group not to attempt the treacherous crossing.

However, Ms Wilkin-Shaw is now appealing Mr Justice Owen's decision, claiming he wrongly evaluated the evidence in relation to "navigational errors" during the course of the tragic day.

The court heard Charlotte died after she and her friends reached Watern Tor in a shivering and desperate state and were advised by a kindly Scout master to press on and cross the brook where she came to grief. That "bad advice" played a part in the tragedy, the judge ruled.

A teacher tasked with meeting the children at Watern Tor never reached her rendezvous after losing her way en route, and that is now the focus point of Mrs Wilkin-Shaw's appeal with her QC, Dr Michael Powers, arguing the navigational blunder amounted to negligence.

However defence QC, Ronald Walker, insisted that the teacher was not incompetent.

"She had no responsibility for accompanying them on the final leg of their journey – still less for safeguarding them from whatever hazards they might encounter after she had checked them," he told the court.

Lords Justice Pill and Moore-Bick and Lady Justice Black reserved their decision on the mother's appeal until a later date.